Filetype
We have developed a prognostic index model for survival data based on an ensemble of artificial neural networks that optimizes directly on the concordance index. Approximations of the c-index are avoided with the use of a genetic algorithm, which does not require gradient information. The model is compared with Cox proportional hazards (COX) and three support vector machine (SVM) models by Van Bel
The mean field theory approach to knapsack problems is extended to multiple knapsacks and generalized assignment problems with Potts mean field equations governing the dynamics. Numerical tests against 'state of the art' conventional algorithms shows good performance for the mean field approach. The inherently parallelism of the mean field equations makes them suitable for direct implementations i
Galactic Archaeology is the study of the formation and evolution of the Milky Way through the properties of stars and stellar populations. The combination of stellar ages, chemical compositions, positions, and velocities can reveal the history of star formation and chemical enrichment in different regions of the Galaxy. A large number of stellar spectroscopic, photometric, and astrometric surveys
In this thesis, a Glauber Monte-Carlo event generator is developed and used to analyze proton-Ion (p -$^{63}$Cu and p -$^{197}$Au) and Ion-Ion ($^{63}$Cu -$^{63}$Cu and $^{197}$Au -$^{197}$Au) collisions. Three different sub-collision models are implemented, the black disk, grey disk and oscillating grey disk models, and their validity is compared. The predicted nucleon-nucleon cross-sections by t
Centre for Mathemat ica l Sc iences Div is ion of Mathemat ics and Numerica l Analys is Course Analysis for MATA21 Analysis in One Variable, Spring 2023 Course Information Lecturer: Jan-Fredrik Olsen Teaching assistants: Joakim Cronvall, Alex Bergman Number of students: 82 newly registered and 20 re-registered. 30 students answered the course evaluation, of which 23 are enrolled on BSc Physics and
https://www.maths.lu.se/fileadmin/maths/Matematik_NF/Kursutvaerderingar/VT2023/MATA21VT23.pdf - 2026-05-23
Lupin Guide: Confirm delivery Support: https://www.staff.lu.se/ Lupin Proceedo Confirm delivery Tabel of Contents Confirm delivery .......................................................................................................... 1 Awaiting order response confirmation ........................................................................ 2 Waiting for order confirmation .................
https://www.ekonomiwebben.lu.se/sites/ekonomiwebben.lu.se/files/2025-03/guide-lupin-proceedo-confirm-delivery.pdf - 2026-05-25
Det finns åtta planeter i bana runt vår egen stjärna Solen och flera dvärgplaneter. Astronomer har numera upptäckt avlägsna exoplaneter kretsande runt andra stjärnor i vår galax Vintergatan. Här lyfter vi blicken upp och beundrar nattens alla stjärnor och stjärnbilder och följer astronomerna på deras upptäcktsfärd bland avlägsna exoplaneter.Orbiting our star, the Sun, there are eight planets and several dwarf planets. Astronomers have now discovered planets orbiting several nearby stars in our galaxy, the Milky Way. In this planetarium show we look up into the starry night sky, familiarize ourselves with the stars and the constellations, and together we discover the exoplanets out there and how they can be detected.
This paper is a write-up of the ideas that were presented, developed and discussed at the third International Workshop on QCD Challenges from pp to A–A, which took place in August 2019 in Lund, Sweden (Workshop link: https://indico.lucas.lu.se/event/1214/). The goal of the workshop was to focus on some of the open questions in the field and try to come up with concrete suggestions for how to make
A feed-forward neural network method is developed for reconstructing the invariant mass of hadronic jets appearing in a calorimeter. The approach is illustrated in W→qq, where W-bosons are produced in pp reactions at SPS collider energies. The neural network method yields results that are superior to conventional methods. This neural network application differs from the classification ones in the
A model for total cross sections with virtual photons is presented. In particular γ*p and γ*γ* cross sections are considered. Our approach extends on a model for photoproduction, where the total cross section is subdivided into three distinct event classes: direct, VMD and anomalous. With increasing photon virtuality, the latter two decrease in importance. Instead Deep Inelastic Scattering dominat
När vi tittar upp mot natthimlen för att utforska stjärnorna i rymden, så är stjärnspektroskopi ett av de främsta medlen. Med hjälp av den metoden kan vi komma fram till vilka kemiska element en stjärna består av, och eftersom en stjärnas sammansättning i stort sett inte förändras över tiden, därmed få en bild av vilka kemiska element stjärnan bestod av när den föddes. Naturvetenskapliga teorier hA major avenue in the study of the Galaxy is the investigation of stellar populations and Galactic chemical evolution by stellar spectroscopy. Due to the dust obscuration in the line-of-sight, stars in the plane and toward the centre of the Galaxy can only be observed in the near-IR wavelength region. Important questions can thus be addressed by observing stars in the near-IR, a field that is in r
Organisationer väljer idag i större utsträckning att övergå från traditionella medier till digitala plattformar för att kommunicera sin varumärkesidentitet. Digital marknadsföring ger organisationer möjlighet att nå ut till en stor publik, kommunicera sitt varumärke och lyfta upp deras värderingar. I samband med denna utveckling har organisationer idag ett större behov av att differentiera sig fråOrganizations are increasingly choosing to switch from traditional media to digital platforms to communicate their brand identity. Digital marketing gives organizations the opportunity to reach out to a larger audience, communicate their brand and express their values. In coherence with this development, organizations have a greater need to differentiate themselves from competitors and take action
Quantum key distribution (QKD) is a secure encryption key generation process to be used by two users in the presence of an eavesdropper. The no-cloning theorem allows the sender "Alice" to securely send qubits with single photons to the receiver "Bob". However, due to real-life imperfections, it is not always possible to have a single-photon source with its properties matching Since the dawn of the first civilizations, the security of information has proven vital to the success of any given community. History records the first attempts at using cryptography techniques in a 1900 BC to 600 BC time frame. In ancient times, the working mechanism of this technique involved the use of letters in the alphabet. To secure the information, these techniques shifted the letters’ nu
I Sverige finns ingen författningsreglerad minimilön eller möjlighet att göra kollektivavtal allmängiltiga. Istället är det arbetsmarknadens parter som tillsammans förhandlar fram kollektivavtalets innehåll om löner och andra anställningsvillkor. Den svenska arbetsrätten har en tradition av långtgående fackligt inflytande och avsaknad av statlig inblandning. Staten har uttryckt att författningsregIn Sweden, there is an absence of a minimum wage legislation. The terms and conditions for most workers is constituted in the collective agreement, made by the parties of the Swedish labour market. The government has expressed itself unable to legislate in the matter as it would mean a violation to the “Swedish labour model”, keeping its neutral policy intact. The collective agreement has a very s
Exact analytical expressions for the ∆S = 1 coupling Im GE in terms of observable spectral functions are given. This coupling determines the size of the ∆I = 3/2 contribution to ε′ . We show analytically how the scheme-dependence and scale dependences vanish to all orders in 1/Nc and NLO in αS explicitly both for Q7 and Q8 . Numerical results are derived for both Q7 and Q8 from the τ-data and know
We use observations of M3 to constrain thermohaline mixing. This is done by matching [C/Fe] and [N/Fe] along the RGB of M3. We find our models can explain observations if it is assumed there is a spread of ∼ 0.3 - 0.4 dex in [C/Fe] in the stars in M3 from their birth. We reproduce the full spread in [C/Fe] at the tip of the RGB. Thermohaline mixing can produce a significant change in [N/Fe] as a f
We propose that a radiative cycle operates in atoms and ions located ina rarefied gas in the vicinity of a hot star. Besides spontaneoustransitions the cycle includes a stimulated transition in one very weakintermediate channel. This radiative bottleneck creates apopulation inversion, which for an appropriate column density results inamplification and stimulated radiation in the weak transition. T
We provide magnitude and color transformations between two near-infrared photometric systems, 2MASS and SIRIUS, the latter currently implemented with the three-Channel SIRIUS camera on 1.4 m Infrared Survey Facility telescope at the South African Astronomical Observatory. The transformation equations are derived using a carefully selected sample of 32 770 stars in the. Large and Small Magellanic C
Unsteady wind loads due to turbulence within the telescope enclosure are one of the largest dynamic disturbances for ground-based optical telescopes. The desire to minimize the response to the wind influences the design of the telescope enclosure, structure, and control systems. There is now significant experience in detailed integrated modeling to predict image jitter due to wind. Based on this e
A stochastic background of gravitational waves is expected to arise from a superposition of many incoherent sources of gravitational waves, of either cosmological or astrophysical origin. This background is a target for the current generation of ground-based detectors. In this article we present the first joint search for a stochastic background using data from the LIGO and Virgo interferometers.
